Chromatographic procedures for the isolation of plant steroids

In this review, we consider the general principles and specific methods for the purification of different classes of phytosteroids which have been iso lated from plant sources: brassinosteroids, bufadienolides, cardenolides, c ucurbitacins, ecdysteroids, steroidal saponins, steroidal alkaloids, verteb rate-type steroids and withanolides. For each class we give a brief summary of the characteristic structural features, their distribution in the plant world and their biological effects and applications. Most classes are asso ciated with one or a few plant families, e.g., the withanolides with the So lanaceae, but others, e.g., the saponins, are very widespread. Where a comp ound class has been extensively studied, a large number of analogues are pr esent across a range of species. We discuss the general principles for the isolation of plant steroids. The predominant methods for isolation are solv ent extraction/partition followed by column chromatography and thin-layer c hromatography/HPLC. (C) 2001 Elsevier Science B.V. All rights reserved.